dhutch
|
| posted on 1/3/09 at 12:21 PM |
|
|
Reversing light
Trying to track down the cause of a non-functional reverse light.
- How would it typicaly be wired? Trying to match up colours and gauges of wire and work out whats going on.
Got the plug of the gearbox switch, that works. No voltage on eather of the pins of the plug, no current between then went shorted together. Although
one appears to be earthed, baddly, or through the revlamp itself.
I would naterally presume there was a relay involved, but given how few relays there are in the car, im less sure.
How likely is it that you would simply run a 12v feed to the switch, and run that onto the rev light?
Daniel
|
|
|
|
|
adithorp
|
| posted on 1/3/09 at 12:25 PM |
|
|
Usually 12v from ignition switched feed via fuse to switch terminal, second switch terminal to the lamp, then to earth.
"A witty saying proves nothing" Voltaire
http://jpsc.org.uk/forum/
|
|
|
omega0684
|
| posted on 1/3/09 at 12:30 PM |
|
|
i have 12v feed to one side of the type 9 gearbox switch, then other side of switch to the rev light then other side of light to earth, when you put
it in reverse the light comes on. hey presto!
|
|
|
omega 24 v6
|
| posted on 1/3/09 at 12:34 PM |
|
|
What he ^^^^^^^ said. The poor earth through the bulb your speaking about is it because your metering from the gearbox plug pin to ground and taking
in the resistance of the bulb filament ??? probably around 2 ohms ish.
Check all your fuses or you have a broken feed wire. try a wire from the battery through a fuse to the ouput pin of the gearbox switch to check if the
circuit beyond the switch is OK then try it to the input with the switch in place on the box to test the switch. It's most likely 100 % an input
problem from your description on your diagnosis though.
If it looks wrong it probably is wrong.
|
|
|
dhutch
|
| posted on 1/3/09 at 12:47 PM |
|
|
quote:
Originally posted by adithorp
Usually 12v from ignition switched feed via fuse to switch terminal, second switch terminal to the lamp, then to earth.
Right, spot on, thats
works.
quote:
Originally posted by omega 24 v6 The poor earth through the bulb your speaking about is it because your metering from the gearbox plug
pin to ground and taking in the resistance of the bulb filament ???
Yes, that was my assumtion.
I will try and trace why theres no 12v at the other pin then.
- All fuses, and bulb, are intact.
Daniel
[Edited on 1/3/2009 by dhutch]
|
|
|
:{THC}:YosamiteSam
|
| posted on 1/3/09 at 04:08 PM |
|
|
if its a type 9 then i would ask - have i the correct plug on the reverse switch? they can lose connection very easily - i didnt have enuff room on
the dax and had to use 2 female bullet crimps - they didnt stay on long due to the movement.. that would be my first look - how good is the
connection? then bulb - is the contact on the end of the bulb actually touching the bulb? blown bulb?
|
|
|
RoadkillUK
|
| posted on 1/3/09 at 10:53 PM |
|
|
quote:
Originally posted by :{THC}:YosamiteSam
i didnt have enuff room on the dax and had to use 2 female bullet crimps - they didnt stay on long due to the movement
Mine was similar but I had to grind down the pins and solder some trialing wires on.
Also as mentioned above, 12v to the switch, and the bulb is earthed.
Roadkill - Lee
www.bradford7.co.uk
Latest Picture (14 Sept 2014)
|
|
|
dhutch
|
| posted on 2/3/09 at 12:23 AM |
|
|
Yes, mine also makes use of two female bullets, which where a squeese to get off. But the appear in good condition.
- The switch as i say is confirmed to work, there is no voltage present at the switch (ignition on) and putting a voltage onto the pins doesnt light
the lamp eather.
Will investigate fully later in the week hopfully.
Is a reversing light need for the MOT? As this is one of the main reasons i have for geting it fixec. That and it will forever bug me on a OCD sort of
leval.
Daniel
|
|
|
RoadkillUK
|
| posted on 2/3/09 at 10:22 PM |
|
|
I don't understand why you wouldn't be getting the light working if you put 12v on the switch.
It's a simple circuit. Battery - Fuse - Switch - Bulb - Earth. Other than that, your wiring is faulty (I'd check the earth connection).
Get a multimeter on the switch and the chassis, see if you get a circuit.
Roadkill - Lee
www.bradford7.co.uk
Latest Picture (14 Sept 2014)
|
|
|
